# Theory of Machines - 2 - Mechanical Engineering (MCQ) questions and answers

1)   Maximum efficiency of spiral gears is given as
- Published on 07 Aug 15

a. [cos ( θ + Φ) + 1] / [ cos ( θ – Φ) + 1]
b. [cos ( θ + Φ) – 1] / [ cos ( θ – Φ) – 1]
c. [sin ( θ + Φ) – 1] / [ cos ( θ – Φ) – 1]
d. [sin ( θ + Φ) – 1] / [ sin ( θ – Φ) – 1]
 Answer  Explanation  Related Ques ANSWER: [cos ( θ + Φ) + 1] / [ cos ( θ – Φ) + 1] Explanation: No explanation is available for this question!

2)   Which type of gears have point contact between two mating gears?
- Published on 07 Aug 15

a. Helical gears
b. Spiral gears
c. Both a. and b.
d. None of the above
 Answer  Explanation  Related Ques ANSWER: Spiral gears Explanation: No explanation is available for this question!

3)   Which of the following statements is/are true?
- Published on 07 Aug 15

a. Lead angle of worm and spiral angle of worm wheel should be equal
b. Worm and worm gear have shaft angle of 90o
c. Helical gears have opposite hand of helix when two teeth mesh
d. All of the above
 Answer  Explanation  Related Ques ANSWER: All of the above Explanation: No explanation is available for this question!

4)   Determine axial force acting on bevel gears when tangential force of 2700 N acts on it.

Pitch cone angle = 12.36o & Pressure angle = 30o

- Published on 07 Aug 15

a. 295.82 N
b. 333.67 N
c. 347.26 N
d. insufficient data
 Answer  Explanation  Related Ques ANSWER: 333.67 N Explanation: No explanation is available for this question!

5)   If lead angle of worm is 13o and lead of worm is 40 mm. Find pitch circular diameter of worm
- Published on 07 Aug 15

a. 53.22 mm
b. 55.15 mm
c. 27.67 mm
d. None of the above
 Answer  Explanation  Related Ques ANSWER: 55.15 mm Explanation: No explanation is available for this question!

6)   Which motion of follower is best for high speed cams?
- Published on 07 Aug 15

a. SHM follower motion
b. Uniform acceleration and retardation of follower motion
c. Cycloidal motion follower
d. All of the above
 Answer  Explanation  Related Ques ANSWER: Cycloidal motion follower Explanation: No explanation is available for this question!

7)   Which of the following statements is false for SHM follower motion?
- Published on 07 Aug 15

a. SHM can be used only for moderate speed purpose
b. The acceleration is zero at the beginning and the end of each stroke
c. The jerk is maximum at the mid of each stroke
d. Velocity of follower is maximum at the mid of each stroke
 Answer  Explanation  Related Ques ANSWER: The acceleration is zero at the beginning and the end of each stroke Explanation: No explanation is available for this question!

8)   Which of the following conditions can be used to minimize undercutting in cam and follower mechanism?
- Published on 07 Aug 15

a. By using larger roller diameter
b. By using internal cams
c. By decreasing the size of the cam
d. All of the above
 Answer  Explanation  Related Ques ANSWER: By using internal cams Explanation: No explanation is available for this question!

9)   Which of the following equation is used to measure pressure angle between direction of follower motion and force exerted by the cam on follower when eccentricity is zero?

Where,
y = displacement of follower

- Published on 07 Aug 15

a. cot Φ = (dy /dθ) / ( rb + y)
b. tan Φ = (dy /dθ) / ( rb + y)
c. tan Φ = (dy /dθ) x ( rb + y)
d. cot Φ = (dy /dθ) x ( rb + y)
 Answer  Explanation  Related Ques ANSWER: tan Φ = (dy /dθ) / ( rb + y) Explanation: No explanation is available for this question!

10)   Calculate the limiting speed to avoid cam jump, if an eccentric plate circular cam has eccentricity of 30 mm and provides motion to the follower of 4 kg mass. Stiffness of the spring is 30 N/mm2. Preload in the spring is 600 N
- Published on 07 Aug 15